Cap and can assembly



25? c. w. HEiNLE 3,1453% CAP AND CAN ASSEMBLY Filed May 4, 1961 2 Sheets-Sheet 1 ATTOR/VfYS 25, 194 c. w. HEINLE 3,14,73

, CAP AND CAN ASSEMBLY Filed May 4, 1961 IIIU INVENTOR. 6/41?! WAX/4M i/f/fl/lf BY gig United States Patent Patented Aug. 25, 1964 3,145,873 CAP AND CAN ASSEMBLY Carl W. I-Ieinle, Short Hills, N.J., assignor to American Can Company, New York, N.Y., a corporation of New Jersey Filed May 4, 1961, Ser. No. 107,719 1 Claim. (Cl. 220-60) The present invention relates to an assembly comprising a can and an overcap in snap engagement therewith and to the method of and apparatus for manufacturing the overcap.

One of the objects of the present invention is to provide a can and overcap assembly in which the overcap is nearly the same outer cross dimension as the can in order to enhance the appearance of the finished package and to provide a stable base for the stacking of one package upon another.

Another object of the present invention is to provide a generally straight wall cap with snap engagement on the dome or breast of a can end wherein the cap and can have approximately the same diameters and the cap extends into a countersink in the can end.

A further object is to provide a cap with means capable of springingly holding it in snapped engagement with the breast of a can of generally the same diameter as the cap.

-A still further object is to provide a method of and apparatus for manufacturing the overcap from a single piece of material.

Numerous other objects and advantages of the invention will be apparent as it is better understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

FIGURE 1 is an elevational view of an assembly illus' trating the features of the present invention.

FIGURE 2 is an exploded view partly in section of the cap and can of FIGURE 1;

FIGURE 3 is a view taken along line 33 of FIG- URE 2;

FIGURE 4 is a view taken along the line 44 of FIG- URE 1;

FIGURE 5 is a view taken along the line 55 of FIG- URE 1;

FIGURE 6 is a top view of apparatus used in making the overcap;

FIGURE 7 is a cross sectional view taken along the line 7-7 of FIGURE 6;

FIGURE 8 is a cross sectional view taken along the line 88 of FIGURE 7;

FIGURE 9 is an exploded view of parts used in the apparatus of FIGURE 6;

FIGURE 10 is a fragmentary enlargement of a portion of the apparatus of FIGURE 7 and FIGURE 11 is a fragmentary enlargement of a portion of the apparatus of FIGURE 7.

The preferred example of an article 9 of manufacture constructed in accordance with the present invention is illustrated in the drawings as comprising a can 10 and an overcap 11. FIGURE 1 illustrates a stack of such articles 9 on one of which a seal band 12 extends about the can 1% and overcap 11.

The preferred embodiment illustrates the can 10 and overcap 11 as being of generally cylindrical construction. It is understood, however, that the can and overcap may be of rectangular, triangular or other cross sectional shape commonly used in the making of cans and caps therefor.

The can 10 has a cylindrical body 13 and an end closure 14 secured to said body to enclose one end of the cylindrical body 13. End closure 14 includes a peripheral end seam portion 15 having a conical inner surface 16 with a large diameter end 16a and a small diameter end 1612 disposed internally of large diameter end 16a and the can body 13. The end closure 14 also includes a modified cone shaped dome portion or breast 18 having an outer surface 19 concentric with the conical inner surface 16 of the end seam portion 15. The end closure 14 further includes a countersunk annular bottom wall 20 curvingly merged into the dome portion or breast 18 and into the end seam portion 15 and extending therebetween. The dome portion 13 has a shallow external annular bead 21 located within the confines of the cone shaped surface 16 of the end seam portion 15 and at a distance from said countersunk annular bottom wall 20. The dome portion or breast 18 also has an external diameter less than the internal diameter of the small end 16b of the cone shaped inner surface 16 of the end seam portion 15 by an amount approximately equal to twice the axial length of that cone shaped inner surface 16.

The overcap 11 has top peripheral portion 24 and a skirt or cylindrical outer wall 25 integrally joined thereto and extending axially therefrom. This peripheral portion 24 is fiat, contiguous to the cylindrical wall portion or skirt 25 and extends over or covers the breast 18. The peripheral portion is at least nearly as large as the can body in cross dimension thereby to permit stable stacking of the articles as illustrated in FIGURE 1.

The outer wall 25 has an external diameter approximately equal to the diameter of the small end 16!) of the cone shaped inner surface 16 of the end seam portion 15 and less than the diameter of the large end 16a of the cone shaped inner surface 16 of the end seam portion 15. The overcap 11 also has an inwardly curved or necked in portion 26 merging with and extending from the cylindrical outer wall portion 25 and terminating in an inwardly curled rim or curl 27 in snap spring engagement with the dome portion or breast 18 at a location between the shallow bead 21 and the countersunk annular bottom wall 21). The inwardly curled rim 2'7 and the inwardly curved or necked in portion 26 hold the skirt or cylindrical outer wall portion 25 of the overcap out of physical engagement with said inner surface 16 of the end seam portion 15, thereby to prevent the outer surface 28 of the skirt 25 of overcap 11 and the inner surface 16 of the end seam 15 from contacting and marring each other when the overcap is mounted on or removed from the dome portion 18.

The incurled rim 27 has alternately spaced portions 30 and 31 disposed end to end in an endless fashion peripherally about the breast 18 and internally of the necked in portion 26. As illustrated in FIGURE 3 the portions 30 lie along arcs of a rim circle of one rim radius r or diameter whose center is on the axis of the outer wall 25 and the cap. The portions 31 lie along arcs of a rim circle having a rim radius r or diameter slightly smaller than the circle defining the rim arcs for portions 30. Thus in effect it might be said that the spaced portions 30 and 31 are different diameters with the alternate portions 30 being of the larger rim diameter and the innermost alternate portions 31 being of smaller rim diameter so as to engage the breast 18. The portions 30 are free from engaging the breast 18.

In addition, and as illustrated in FIGURES 4 and 5 the portions 30 and 31 of curled rim 27 have the same curl radius r or diameter. This curl radius 1- is the radius from a point entirely within the curl or curled rim 27 to that portion of the outer surface of the curl which engages the breast 18 under the bead 21. As illustrated in FIGURE 4, each of the curl portions 31 is resilient and has a short relatively straight portion X positioned between the remainder of the curl portion 31 and the necked in portion 26. The length of this straight portion, when taken along rim radius r is equal to the difference between the rim radius r and r The presence of this straight portion X in each curl portion 31 projects the curl portions 31 inwardly of the curl portions 30 so that the curl portions 31 engage the breast 13. The portions 30 are free from engaging breast 18 and are resilient and thus deformable from their respective normal arc formations during capping of the overcap onto the breast. After the portions 31 have snapped over the shallow bead they engage the breast 18 between the shallow bead 21 and the annular bottom wall 20.

The curl radius r;; is as small as can be manufactured conveniently so as to provide the outer surface of the curl free from wrinkles and other unwanted deformations. In this instance the curl radius r is less than /2 the distance between the bead 21 and the annular bottom wall and greater than the length of the straight portion X. The curl portions and 31 of different rim diameters but of the same curl radius are thus formed in alternate repetitive fashion in an endless chain with practically no rough or wrinkled scratch or mar producing shoulders at the points of juncture 32 where contiguous portions 30 and 31 meet each other.

The inturned or necked in portion 26 and the curled rim 27 are formed by a punch and die manufacturing apparatus 35 illustrated in FIGURES 6 to 11. This punch and die apparatus 35 comprises a punch 36 and a cap holding die 37 cooperatively aligned therewith for relative movement towards and away from each other in the manner commonly used in stamping or pressing operations. In this instance the die 36 is provided with curl forming surfaces and is constructed from forming members 38 and 39.

The forming member 38 has spaced forming fingers 40 each provided with a surface 41 contoured to the desired outer surface of the curled portion 31 and the adjacent portion of the necked in portion 26. As previously described these forming fingers 40 are spaced apart and extend radially outwardly. For purposes of description this surface 41 may be divided into a surface portion 41a which forms the curl portion 31, a surface portion 41b which forms the contiguous or attached necked in portion 26 and a surface portion 410 which blends with the necked in portion and sizes the outer surface of the outer wall portion 25. In addition, it is noted that the surface portion 41a has a flat portion 41d to form the flat portion x as illustrated in FIGURE 4.

Forming member 39 has insert forming fingers portions 42 alternatively insertable between the respective forming fingers 40 to cooperate therewith to form the complete annular die for forming the endless curl 27. As best illustrated in FIGURES 8 and 11 each insert forming portion 42 sits tightly between its next adjacent of forming fingers 40.

Forming member 38 and forming member 39 may be secured together by bolts 45 or other suitable means as illustrated in FIGURE 6. In addition punch and die ap- A. paratus 35 may be provided with a suitable mechanism 46 to strip the overcap fromfingers 40 and insert forming portions 42 after curl 27 has been formed.

The forming portions 42 are each provided with a surface 43 contoured to the desired outer surface of the curl portion 30 and the adjacent contiguous portion of the necked in portion 26. For purposes of description this surface 43 may be divided into a surface portion 43a which forms the curl portion 30, a surface portion 43b which forms the contiguous or attached necked in portion 26 and a surface portion 41c which blends with the necked in portion and sizes the outer surface of the outer wall portion 25.

In operation a cup shaped member or work piece is inserted in cap holding die 37. Following this die apparatus 35 and cap holding die 37 are moved towards each other to force the outer wall of the workpiece along surface portions 41c and 43c until the then free raw edge has followed progressively along the surfaces 41 and 43 until they are formed into portions 26 and the curl 27. For example, in forming the rim portion 31 the raw edge of the material passes progressively upwardly in FIGURE 10 along the surfaces 410, 41b and 41a including 41d. Surface 41c sizes the outer wall 25. Surface 41b forms the necked in portion 26 and surfaces 41a and 41d form the curl portion 31. Similarly, the surfaces 43a, 43b and 43c form the curl in portion 30 and its next adjacent part of necked in portion 26 and outer wall 25. All of the surface portions 410 and 430 are arranged in endless end to end fashion to form a circle. Similarly, all of the surfaces 41b and 43b are arranged end to end in fashion wherein they merge with each other to form a smooth outer surface. However, as best illustrated in FIGURE 8 the surfaces 41a and the surfaces 43:: are arranged at different distances from the axis of the circle on which surfaces 430 and 410 lie so as to provide the portions 30 and 31 with different rim diameters. After the curl 27 and the necked in portion 26 have been formed and the outer wall 25 sized die apparatus 35 and cap holding die 37 are separated and mechanism 46 assures removal of a completed overcap 10 from die apparatus 35. The completed overcap 10 thus has the configuration as previously described so that it will snappingly engage the breast 18 and provide for suitable stacking of the articles 9.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description and it will be apparent that various changes may be made in the form, construction, and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

An article of manufacture comprising a can and an overcap on said can, said can having a body and an end closure secured to said body to enclose one end of said body, said end closure including a peripheral end seam portion having an inner surface disposed internally of said can body, said end closure also including a dome portion having an outer surface spaced from and within the surface of the end seam portion, said end closure further including a countersunk bottom wall curvingly merged into said dome portion and into said end seam portion and extending therebetween, said dome portion having a shallow external bead located within the confines of the surface of the end seam portion and at a distance from said countersunk bottom wall, said overcap having an outer wall of external dimensions approximately equal to but less than the corresponding dimensions of the inner surface of the end seam portion, said overcap having an inwardly curved portion merging with and extending from said outer wall and terminating in an inwardly curled rim having inwardly extending spaced resilient portions in snap spring engagement with said dome portion between said shallow bead and the countersunk bottom wall,

the engagement of said resilient rim portions with said dome portion constituting the sole engagement of said overcap with said can, said inwardly curled rim and said inwardly curved portion holding said outer wall of the overcap out of physical engagement with said inner surface of the end seam portion, thereby to prevent the outer surface of said overcap and the inner surface of said end seam from contacting and marring each other when said overeap is mounted on or removed from said dome portion.

References Cited in the file of this patent UNITED STATES PATENTS Punte Dec. 26, 1933 Williams Sept. 28, 1937 Bauman Nov. 10, 1942 Geertserna May 9, 1944 Lauve Oct. 1, 1946 Fralick Aug. 25, 1959 Taylor May 1, 1962 

